import sys
from operator import methodcaller
import re
def main():
cypherTexts = []
# cyphertext 1 (0)
cypherTexts.append("315c4eeaa8b5f8aaf9174145bf43e1784b8fa00dc71d885a804e5ee9fa40b16349c146fb778cdf2d3aff021dfff5b403b510d0d0455468aeb98622b137dae857553ccd8883a7bc37520e06e515d22c954eba5025b8cc57ee59418ce7dc6bc41556bdb36bbca3e8774301fbcaa3b83b220809560987815f65286764703de0f3d524400a19b159610b11ef3e")
# cyphertext 2 (1)
cypherTexts.append("234c02ecbbfbafa3ed18510abd11fa724fcda2018a1a8342cf064bbde548b12b07df44ba7191d9606ef4081ffde5ad46a5069d9f7f543bedb9c861bf29c7e205132eda9382b0bc2c5c4b45f919cf3a9f1cb74151f6d551f4480c82b2cb24cc5b028aa76eb7b4ab24171ab3cdadb8356f")
# cyphertext 3 (2)
cypherTexts.append("32510ba9a7b2bba9b8005d43a304b5714cc0bb0c8a34884dd91304b8ad40b62b07df44ba6e9d8a2368e51d04e0e7b207b70b9b8261112bacb6c866a232dfe257527dc29398f5f3251a0d47e503c66e935de81230b59b7afb5f41afa8d661cb")
# cyphertext 4 (3)
cypherTexts.append("32510ba9aab2a8a4fd06414fb517b5605cc0aa0dc91a8908c2064ba8ad5ea06a029056f47a8ad3306ef5021eafe1ac01a81197847a5c68a1b78769a37bc8f4575432c198ccb4ef63590256e305cd3a9544ee4160ead45aef520489e7da7d835402bca670bda8eb775200b8dabbba246b130f040d8ec6447e2c767f3d30ed81ea2e4c1404e1315a1010e7229be6636aaa")
# cyphertext 5 (4)
cypherTexts.append("3f561ba9adb4b6ebec54424ba317b564418fac0dd35f8c08d31a1fe9e24fe56808c213f17c81d9607cee021dafe1e001b21ade877a5e68bea88d61b93ac5ee0d562e8e9582f5ef375f0a4ae20ed86e935de81230b59b73fb4302cd95d770c65b40aaa065f2a5e33a5a0bb5dcaba43722130f042f8ec85b7c2070")
# cyphertext 6 (5)
cypherTexts.append("32510bfbacfbb9befd54415da243e1695ecabd58c519cd4bd2061bbde24eb76a19d84aba34d8de287be84d07e7e9a30ee714979c7e1123a8bd9822a33ecaf512472e8e8f8db3f9635c1949e640c621854eba0d79eccf52ff111284b4cc61d11902aebc66f2b2e436434eacc0aba938220b084800c2ca4e693522643573b2c4ce35050b0cf774201f0fe52ac9f26d71b6cf61a711cc229f77ace7aa88a2f19983122b11be87a59c355d25f8e4")
# cyphertext 7 (6)
cypherTexts.append("32510bfbacfbb9befd54415da243e1695ecabd58c519cd4bd90f1fa6ea5ba47b01c909ba7696cf606ef40c04afe1ac0aa8148dd066592ded9f8774b529c7ea125d298e8883f5e9305f4b44f915cb2bd05af51373fd9b4af511039fa2d96f83414aaaf261bda2e97b170fb5cce2a53e675c154c0d9681596934777e2275b381ce2e40582afe67650b13e72287ff2270abcf73bb028932836fbdecfecee0a3b894473c1bbeb6b4913a536ce4f9b13f1efff71ea313c8661dd9a4ce")
# cyphertext 8 (7)
cypherTexts.append("315c4eeaa8b5f8bffd11155ea506b56041c6a00c8a08854dd21a4bbde54ce56801d943ba708b8a3574f40c00fff9e00fa1439fd0654327a3bfc860b92f89ee04132ecb9298f5fd2d5e4b45e40ecc3b9d59e9417df7c95bba410e9aa2ca24c5474da2f276baa3ac325918b2daada43d6712150441c2e04f6565517f317da9d3")
# cyphertext 9 (8)
cypherTexts.append("271946f9bbb2aeadec111841a81abc300ecaa01bd8069d5cc91005e9fe4aad6e04d513e96d99de2569bc5e50eeeca709b50a8a987f4264edb6896fb537d0a716132ddc938fb0f836480e06ed0fcd6e9759f40462f9cf57f4564186a2c1778f1543efa270bda5e933421cbe88a4a52222190f471e9bd15f652b653b7071aec59a2705081ffe72651d08f822c9ed6d76e48b63ab15d0208573a7eef027")
# cyphertext 10 (9)
cypherTexts.append("466d06ece998b7a2fb1d464fed2ced7641ddaa3cc31c9941cf110abbf409ed39598005b3399ccfafb61d0315fca0a314be138a9f32503bedac8067f03adbf3575c3b8edc9ba7f537530541ab0f9f3cd04ff50d66f1d559ba520e89a2cb2a83")
# cyphertext target (10)
cypherTexts.append("32510ba9babebbbefd001547a810e67149caee11d945cd7fc81a05e9f85aac650e9052ba6a8cd8257bf14d13e6f0a803b54fde9e77472dbff89d71b57bddef121336cb85ccb8f3315f4b52e301d16e9f52f904")
# convert all to ASCII
cypherTextsDecoded = map(methodcaller("decode", "hex"), cypherTexts)
# chose two to XOR
## This part of the program is interactive.
## Keep guessing cribs and see how they might match in various XOR-ed cyphertexts (== XOR-ed plaintext)
## Finally choose the longest, fully decrypted crib (6) and the target cypher (10)
# /begin interactive
crib = "There are two types of cyptography: one that allows the Government to use brute force to break the code, and one that requires the Government to use brute force to break you"
xorTextNum1 = 6
xorTextNum2 = 10
# /end interatcive
xoredText = strxor(cypherTextsDecoded[xorTextNum1], cypherTextsDecoded[xorTextNum2])
# loop all individual positions of the XOR-ed crypto (plain) text
textLength = len(xoredText)
for i in range(textLength):
# XOR the substring with the crib
substrXoredText = xoredText[i:]
cribDraggedText = strxor(substrXoredText,crib)
# do an estimated guess wether the text is readable, if so print the guess (in place)
if(isreadable(cribDraggedText)):
printCodePos(i, cribDraggedText, textLength, '.')
print "\n\nGuess key (when the crib starts lining up):"
key = strxor(cypherTextsDecoded[xorTextNum1], crib)
print "key: %s"%key.encode('hex')
print "\n\nDecrypt all messages using the key:"
for j, cypher in enumerate(cypherTextsDecoded) :
print "[%d] %s" % (j, strxor(cypher, key))
def strxor(a, b): # xor two strings of different lengths
if len(a) > len(b):
return "".join([chr(ord(x) ^ ord(y)) for (x, y) in zip(a[:len(b)], b)])
else:
return "".join([chr(ord(x) ^ ord(y)) for (x, y) in zip(a, b[:len(a)])])
def isreadable(str): # check readability (allow only alphanumeric chars and some punctiation)
return bool(re.search('^[a-zA-Z0-9\., \'\"\-_\:\(\)]+$', str))
def printCodePos(i, code, maxLen, filler): # output the guess in place of the message
prefix = filler*i
ln = len(code)
postfix = filler*(maxLen-i-ln)
print("%s%s%s" % (prefix,code,postfix))
if __name__ == '__main__':
main()